Punching tool



Patented May 19, 1931 STATES FATENT PUNCI-IING TOOL Application filedApril 29,

The present invention relates generally to cutting or punching tools andmore particularly to those tools which are adapted to be used to cutcircular apertures, such, for ex ample, as holt holes in gaskets orstrips of sheet material.

One object of the invention is to provide a punching tool in which themeans for ejecting the circular wads or disks that are punched from thegaskets or strips consists of an elongated spring rubber piece which ispolygonal in cross section and is confined in a cylindrical cavity orsocket in the cutting end of the tool in such a manner that the cornersthereof engage the annular side wall of the socket and consequentlyoperate to hold the ejector-piece in place against accidental outwarddisplacement. 7 Another object of the invention is to provide a tool ofthe aforementioned character in which the operative or lower end of thetool is ground or bevelled internally to form the usual circular cuttingedge and in addition provide a frustoconical chamber or compartmentaround the outer end of the wad-ejecting piece which compartment servesto receive or accommodate the distorted rubber when the piece iscompressed longitudinally during use of the tool.

Another object of the invention is the provision of a supplementalcutting member which is adapted to be sleeved over and secured to thecutting end of the tool and is provided with a cutting edge which coactswith the cutting edge of the tool to form washers or other such ringshaped objects whenthe tool is used for that purpose.

A further object of the invention is to provide a supplemental cuttingmember of the aforesaidtype embodying washer ejector means in the formof a split spring rubber bushing which is held in its operative positionby engaging frictionally the outer periphery of the supplemental cuttingmember.

A still further object of the invention is to provide a punching toolwhich is generally of a new and improved construction, consists of but afew parts and may be manufactured at a low and reasonable cost.

Other objects of the invention and the va- 1929. Serial No. 358,828.

rious advantages and characteristics of the present construction will beapparent from a consideration of the following detailed descrintion.

In the drawings which accompany and form a part of this specification ordisclosure and in which like numerals of reference denote correspondingparts throughout the several views:

Figure l is a longitudinal sectional view of a tool embodying theinvention, illustrating in detail the specific, construction of thesupplemental cutting member and the cutting end of the tool, as Well asthe arrangement and formation of the various spring rubber ejectormeans;

Figure 2 is a View similar to Figure 1 showing the tool and supplementalcutting member in the position that they assume when driven into a pieceof sheet material;

Figure 3 is a perspective of the elongated spring rubber piece whichforms the wadejector means for the cutting end of the tool;

Figure 4 is a transverse section taken on the line 4L-4 of Figure 1,disclosing in detail the manner in which the corners of theejector-piece grip or frictionally engage the cylindrical wall thatforms or defines the socket in the cutting end of the tool; and

Figure 5 is a perspective view of one of the members of the split springrubber bushing which operates as the washer ejectormeans for thesupplemental cutting member.

The invention is exemplified in a tool for use in punching holes insheet material, such, for example, as gasket composition, cork, rubberor fibrous material. This tool comprises an elongated cylindrical body(3 which is preferably formed of tempered steel. The upper end of thisbody forms a handle 7 which is adapted to be held in one hand during useof the tool. The extreme upper end of the body 6 is bevelled, as at 8and terminates in a flat hammering surface or anvil 9. The lower orcutting end 10 of the body is suitably machined so that it is smaller indiameter than the handle 7 and forms a shoulder 11. A cylindrical socketor cavity 12 is drilled or otherwise formed in the cutting end 10. Thiscavity has'an open lower end and isarranged concentrically with respectto the bodyr6. It extends upwardly into the handle 7 as disclosed inFigures 1 and 2. e The extreme lower part' of the cutting end 10 of thetool is bevelled internally to form a circular cutting edge 13. The

latter-is in direct alignment with the outer periphery of the cuttingend 10 and consequently operates, during useof theitool, to cut a holeor aperture of astraight sided character. The bevelled'portion which results in the formation of the cutting edge 13 defines a frusto-conicalchamber, 14 which I hold the piece removably in place. piece 15 ispreferably arranged in the socket extends between said edge and thelower end of the socket 12.

An elongated member or piece 15 serves to eject the wads or disks thatare formed by i the cutting edge 13 when the tool is driven into gasketor other sheet material. This "piece 15 isfformed of spring rubber andis square in cross section as clearly illustrated in Figure 4. Thethickness of. the piece is such that when thepiece is forced into thesocket 12 thegcorner portions 15 thereof engage frictionally thecylindrical'wall that defines or forms the. socket and as a result 12sothat thelower end thereof protrudes .a

short distance beyond the cutting edge 18.-

' shape and thereby forces outwardly the wad \Vhenthe tool isdriveni'nto a gasket or like article the protruding portion as well asthe remainder of the piece, is compressed.

Upon release of the tool the piece 15 due to its resiliencysprings backinto its normal or disk thatis-enibedded or lodged in'the chamber 14 asa result of the tool driving;

operation. The frusto-conical chamber 14 operates to accommodate thedistorted rubher in the'l'ower end of the piece 15. The

'four spaces 12 between the wall of the socket and the sides of thepiece 15 2.CCOII1-' Inodate the distorted rubber of the upper end andcentral portion of said'piece (see Figure2); Acharacteristic andanadvantage of utilizing a sol d spring rubber ejiecti'ngl piece of thetype described is that no lubricant of any sort is'necessary in the use.In addition, the cost of manu-' of" the tool. 7 facture or productionis'reduced to a mini mum for the reason that it is possible toobtaiiiarubber ejector-piece at a low cost and no separate or additionalmeans need be employed for retaining the piece in place. In the eventthe piece 15 wears out or loses its resiliency, it may be withdrawn fromthe socket and replaced by a similar rubber ejector-piece; A pluralityof sheet metal disks 16 are interposed betweenthe inner end of'the piece15"and the top, of the socket 12 By increasing or decreasing'the numberof these disks a change may be eflected in the position of thepiece'relating Said to the socket. In other words, if itshould bedesired to have the outer end of the piece 15 protrude a greaterdistance from the cutting edge 13 one or more disks l 6 will be added tothose already inplace. The addition of these disks. effects acorresponding lowering of the piece relative to the socket When it isdesired to raise the protruding end of the piece 15 with respect to theedge 13 one or inoreof the disksf16 are with- V drawn until thedesiredchange in position is effected. The disks 16 exemplify means ofan improved character whereby the ejector-piece may be adjusted inthe'socket To permit the tool to be used to for ii washers, as well asto make bolt holes in gaskets, a suppleinental'cutting member 17 isprovided. This niember'is of cylindrical conformation and has formed inthe upper part thereof a concentricxbore 18 through which the cuttingend 10 of the body is adapted to' extend.' The member 17 is adapted tobe sleeved over the end portion 10 and shifted upwardly thereon untilarrested by engagement with the'shoulder 11. A set screw 19 operates tohold the'supplemental cut'ting meinber 17 in connected re-. lation withthe body 6. This set screw extends transversely through the upper part 7c of the member 17 and has the inner end thereof shaped to fit in arecess, 20 in thev cutting end 10 of the body. The outer end of thescrew has a kerf 21 whichis adapted to receive the blade of :a screwdriver or a 7 similar turning tool. The inner peripheral part ofthelower part ofthe supplemental cutting member 17 .is cut away to. form anspace 22.. As a result of thisarrangement the aforesaid cutting edgeoperates in conjunction with the edge 13 to" form washers havingstraight sides; A spring rubber bushing 25 is adapted to eject thewashers automaticallyfrom the annular space 22 'afterthey have been cutby the edges 13 and 24. This bushing is positioned" in the space 22 andis split longitudinally so that it is of a twospieceeharacter. Theinside diameter of "the bushing is slightly smaller than that oftheouter periphery of the cutting end 10.;As a result of this arrangementthe ends of'the bushing pieces grip frictionally the end and force thecentral parts of the bushing pieces into frictional engagement with theinner periphery of the member 17. By virtue of the grippingcharacteristics of the bushing, said bushing is held in place againstundesired withdrawal. The length of the bushing is preferably such thatthe lower end terminates slightly outwardly of the cutting edges 13 and24. The upper or inner end of the bushing has V-shaped grooves 26 formedtherein. These grooves permit the rubber to recede into the space 22when the bushing is under compression as a result of use of the tool.The bushing pieces are preferably applied after the member 17 isconnected in place by the set screw 19.

They are assembled by shifting them longitudinally into the space 22.

WVhen the tool is to be used for cutting bolt holes in gaskets, the bodyis used in dependently of the supplemental cutting member 17. Said bodyis used by gripping the handle 7 in one hand and hammering against thesurface 9 so as to drive the cutting end 10 into the gasket which ispreferably placed upon a wooden block. \Vhen the body is driven so thatthe cutting edge 13 has passed completely through the gasket, it iswithdrawn. As soon as the withdrawal takes place the spring rubberejector-piece 15 springs back into its normal position and causesejection of the wad or disk which is lodged in the chamber 14. In theevent the ejector-piece 15 protrudes too far below the cutting edge 13and thereby hampers or hinders operation of the tool, one or more of thedisks 16 are removed so as to adjust the ejector-piece to the properposition.

Nhen the tool is to be used to form washers or other such ring-shapedobjects, a supplemental cutting member 17 is sleeved over the cuttingend 10 and locked in place by means of the set screw 19. The pieces ofthe bushing 25 are then shifted into their operative position ashereinbefore described.

l/Vhen the tool is in its completely assembled position, that is, whenit has attached thereto the supplemental cutting member 17, it isoperated by gripping the handle 7 and hammering the surface 9 so as todrive the tool into the material from which the washers are to be cut.After the tool has been driven the proper distance, it is withdrawn,which action enables the bushing 25 as well as the ejector piece 15 toexpand and thereby eject the washer and wad.

The punching tool herein described is simple as far as construction isconcerned in that it consists of but a few parts. By reason of the factthat the ejector means is made from rubber, the tool may be produced ata comparatively low cost.

The invention is not to be understood as restricted to the details setforth, since these may be modified within the scope of the appendedclaims, without departing from the spirit and scope of the invention.

Having thus described the lnvention, what I claim as new and desire tosecure by Letconsisting of a block of elastic'material located in thesocket, said block being polygonal in cross section and having thecorners thereof engaging frictionally the wall of the body that definesthe socket.

2. A punching tool of the character described, comprising a bodyprovided at one end thereof with a handle and having formed at its otherend a circular cutting edge and a longitudinally extending openendcdcylindrical socket, and a wad ejector consisting of a block of elasticmaterial located in the socket, said block being of square cross sectionand having the corners thereof engaging frictionally the wall of thebody that defines the socket.

3. A punching tool of the character described, comprising a cylindricalbody provided at one end thereof with a handle and having formed at itsother end a longitudinally extending open-ended cylindrical socket, theextreme end portion of said one end of the body being bevelledinternally adjacent the socket to form a circular cutting edge and afrusto-conical chamber communieating with the socket, and a wad ejectorconsisting of a block of elastic material mounted in the socket andpositioned so that the outer end thereof terminates adjacent the cuttingedge, the aforesaid chamber being operative to accommodate the saidouter end of the block when the block is compressed during use of thetool.

4. In a punching tool of the character described, the combination of abody provided at one end thereof with a handle and having at its otherend a pair of circular cutting elements arranged concentrically andspaced apart to form an annular intervening space, and ejector-meansconsisting of a longitudinally split bushing of elastic materialpositioned in the annular space, said bushing being so formed withrespect to inside diameter that the ends of the bushing sections gripfrictionally the outer periphery of the inner cutting element and tendto force the central portions of said sections into frictionalengagement with the inner periphery of the outer cutting element.

5. In a punching tool of the character described, the combination of abody provided at one end thereof with a handle and having at itsotherend apair oiicircular cut- :tingelements arranged concentricallyand "spaced apart to form an annular intervenmg space, and e ector:means COIlSlStlIlg of tions of said sectionsinto frictional engageabushingof elastic material positioned in said annular space and splitlongitudinally into two sections saidbushing being so formed withrespect to inside diameter that the ends of the sections: gripvrfi'ictionailly the outer periphery of the inner cutting element andtend to force the central por mentiwith the inner periphery of the outercutting element.

' said bushing having the inner end thereof it notched .to allow forrecession during use 6. In a punching tool of the character described,the combination of a body provided at one end thereof with a handle andhavingatits other end a pair of circular cutting elements arrangedconcentrically and spaced apart to form an annular inter- 7 ening space,and a spring rubber bushing V positioned in the annular space andoperatiyeto eject ring-shaped wads therefrom,

of theutool.

Signed at Chicago, Illinois, this 18th day of April, 1929. r

WIL iAM s. "siAwLE

